That's exactly what we're trying to do
Came out perfect, actually probably went a bit longer than 4 hours, as I put it on just after lunch to be ready when I got back and then heat back up just before dinner, but was out longer than expected so had about 4hrs45 in total at 73c. Turned out ideal and so soft, for a cheap bit of Aldi meat worked really well.
Did burgers in it last night straight from the freezer, once again came out lovely, although they look so wierd when finished, but quick sear and sorted!
Haggis filled chicken breast to try tonight!